Winch for cargo-retaining strap

ABSTRACT

A winch for a cargo restraining strap includes a frame having a base and first and second parallel spaced sidewalls. The first and second sidewalls define respective first and second apertures. A protective wall extends from the base and is spaced from the first sidewall. The first sidewall and the protective wall cooperate to define a clevis structure including a channel. A pawl is movably secured to the frame, with an inner end thereof located in the clevis channel. A spool extends between the first and second sidewalls and is rotatably supported in the first and second apertures of the first and second sidewalls. A ratchet wheel is connected to the spool and is located adjacent the first sidewall. The ratchet wheel is selectively engaged by the pawl. The frame, spool and ratchet wheel can be defined from aluminum alloy. The frame can be extruded as a one-piece construction. The spool and ratchet wheel can be extruded as a one-piece construction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from and benefit of the filing date ofboth: (i) U.S. provisional application Ser. No. 60/617,867 filed Oct.12, 2004; and, U.S. provisional application Ser. No. 60/664,023 filedMar. 22, 2005, and both of these provisional applications are herebyincorporated by reference into the present specification.

BACKGROUND

FIG. 1 illustrates a known winch 10 for retaining/tightening acargo-retaining strap. The winch 10 comprises a steel frame 20 includinga base 22 having first and second separate base plates 22 a,22 b thatdefine locations L1,L2 for sliding receipt of a double-L track that isconnected to or formed as a part of a cargo trailer or cargo bed, e.g.,as part of a “flat-bed” trailer. First and second parallel legs 24 a,24b are welded to the base 22 and cooperate with the base to define theframe 20 with an inverted U-shaped structure. A spool 26 is rotatablysupported by and between the legs 24 a,24 b and comprises a slot 26 a inwhich a cargo-retaining strap S is inserted and then wound around thespool for storage/use. The strap S is payed-out from the spool 26 asneeded by counter-clockwise rotation of the spool, and retracted asneeded by clockwise rotation of the spool 26. The spool 26 includes adriving head (not shown) that projects outwardly from sidewall 24 b andthat is engaged by a winch bar or other tool to rotate the spool. Aratchet wheel 28 is welded to the spool 26 and rotates therewithadjacent an outer face of sidewall 24 a. A pawl 30 is pivotally securedto the sidewall 24 a by a bolt, pin or other fastener 32 and pivotsbetween a first position, as shown, where it engages the ratchet wheel28 and prevents counter-clockwise rotation of the ratchet wheel 28 andspool 26 but allows clockwise rotation for strap tightening operations,and a second position, where it is disengaged from the ratchet wheel 28to allow free rotation of the ratchet wheel 28 and spool 26 in eitherdirection. The pawl 30 is normally positioned in its first position, asshown, by force of gravity and/or a biasing spring. The base 22 of thewinch 10 can also be configured to mate slidably with a flangedside-rail of a cargo trailer or cargo bed, e.g., of a “flat-bed”trailer.

The winch 10 shown in FIG. 1 has been found to be sub-optimal for avariety of reasons. The frame 20, spool 26, ratchet wheel 28 and pawl 30are defined from ferrous steel and are susceptible to corrosion and canweigh as much as 9 pounds (lbs.) or more. Furthermore, the frame 20,itself, comprises four separate steel pieces (base plates 22 a,22 b,sidewalls 24 a,24 b) that must be arranged properly and then weldedtogether which increases assembly time and cost. Furthermore, the weldzones are susceptible to corrosion and/or failure.

FIG. 2 illustrates another known cargo-strap retaining winch 10′ that isstructured similarly and functions identically to the winch 10. Unlikethe winch 10, however, the winch 10′ comprises a one-piece frame 20′defined from a steel plate that is bent into the required invertedU-shaped structure so as to comprise a base 22′ and first and secondsidewalls 24 a′,24 b′. The locations L1′,L2′ for slidably mating with adouble-L track of a flat-bed trailer or other cargo hauling structure asdescribed above can be machined after the U-shaped frame 20′ is definedor can be defined in the frame-stock prior to the bending operation. Thewinch 10′ comprises a spool 26′, ratchet wheel 28′ and pawl 30′ that areidentical in structure and function to those described above inconnection with FIG. 1. The base 22′ of the winch 10′ can also beconfigured to mate slidably with a flanged side-rail of a cargo traileror cargo bed, e.g., of a “flat-bed” trailer.

The winch 10′ represents an advantage over the winch 10 in terms of thesimplified one-piece structure of the steel frame 20′ which eliminatesall welding operations required to construct the frame 20 of the winch10. Like the winch 10, however, the frame 20′, spool 26′, ratchet wheel28′ and pawl 30′ of the winch 10′ are defined from ferrous steel and, assuch, are susceptible to corrosion in a manner similar to the winch 10and are high-weight, especially in light of the fact that a singletrailer or other cargo bed will typically carry multiple winches, e.g.,ten or more.

Another main disadvantage of the winch 10′, resulting from its one-pieceU-shaped frame 20′, is that the base 22′ of the frame has a maximumpossible width W1 which is only equal to the width W2 definedinclusively between the parallel sidewalls 24 a′,24 b′. This maximumpossible width or “footprint” of the base 22′ has been found to bedeficient for certain applications because the forces exerted on thewinch 10′ by the strap S are undesirably concentrated within the maximumwidth W1 of the base. More particularly, the steel-framed winch 10′ isoften mated with an aluminum structure such as a double-L track, aflanged side-rail, or the like of a cargo trailer, and this mismatch inmaterial hardness and elasticity has been found to result in damage tothe aluminum structure such as, e.g., bending, gouges, and tearing. Thesteel winch frame 20′ has a much higher hardness and lower elasticity ascompared to the aluminum mounting structure of a flat-bed trailer or thelike, and this leads to the noted damage to the aluminum structure. Forexample, 6061-T6 aluminum alloy has a Brinell hardness number (BHN) of95, while Brinell hardness numbers for common steels, such as those usedto manufacture the conventional winches 10,10′, vary between BHN=133 forA569 steel to BHN=250 for A514 and 100XF steels, and BHN=400 for AR400steel. Furthermore, aluminum alloys commonly used in trailer and othercargo bed manufacturing such as, e.g., 6061-T6 extrusions, have amodulus of elasticity that only ⅓ of the modulus of elasticity of steel,i.e., the deflection of an aluminum structure will be three-times thatof a similar steel structure. As such, it can be seen that use of steelwinch structures 10,10′ on an aluminum trailer or cargo bed leads to aninherent mismatch in hardness and elasticity, with the common resultbeing that the steel winch permanently damages the aluminum structure.Given the increasing popularity of flat-bed trailers and cargo bedsdefined entirely from aluminum or having aluminum siderails and/or winchtracks for mating with winches, a need has been identified for a new andimproved winch compatible with these aluminum structures.

A further problem associated with use of steel winches 10,10′ on analuminum alloy trailer or cargo bed is the resulting galvanic or“electrolysis” reaction that occurs between these dissimilar materialsin the presence of an electrolyte, e.g., when wet by humidity or rainwater. This reaction often causes the winches to become stuck on thewinch track in a manner that prevents them from being easily moved tothe required location to adjust the position of the cargo straps. Also,the electrolysis reaction speeds corrosion at the interface of thedissimilar metals due to ion exchange and can lead to severe pitting andfailure.

New ice and snow control techniques have exacerbated the corrosion ofconventional steel winches and also appear to act as a catalyst to thedamaging electrolysis reaction between steel winches and aluminum alloytrailers and cargo beds. These new ice and snow control techniquesinclude use of liquid compounds comprising magnesium chloride or calciumchloride that are many times more corrosive to steel as compared to“road salt” as we know it, e.g., sodium chloride. These new techniquesare becoming more popular due to a cost advantage and are causingextensive damage to steel components of truck trailers. This phenomenonis documented in the article “Corrosion Explosion” appearing in theSeptember 2004 issue of Trailer/Body Builders, pps. 38-45. As such, itis clear that corrosion of conventional steel winches 10,10′ exposed tothese increasingly popular ice/snow control compounds will accelerateand render same unusable and/or unsafe.

Another main disadvantage associated with known winches 10,10′ is thatthe connection between the pawl 30,30′ and the sidewall 24 a,24 a′ frameby a bolt or other fastener 32 connected to the frame 20,20′ can beinsufficient to hold the high-loads imposed on pawl 30,30′ through theratchet wheel 28,28′. In particular, the fastener 32 is subjected tohigh bending and shearing forces that have been found to cause failureof the fastener with the result being an unconstrained ratchet wheel28,28′ and strap S which can lead to loss of the cargo load. As such,improvements have been deemed desirable in connection with theconnection of the pawl 30,20′ to the frame 20,20′ to improve safety.

With reference to FIGS. 2A,2B,2C, the steel frames 20,20′ of the winches10,10′ lead to another safety deficiency in that the winches 10,10′ areoften slidably receivable onto extruded aluminum winch tracks T1,T2,T3such as double-L tracks defined from aluminum extrusions with a loose oruneven fit that results in gaps G1,G1,G3 between the track and the base22,22′ of the winch frame. These gaps have been found to be highlyundesirable in that forces exerted on the winch are not evenlydistributed to the track and are thus more likely to damage the track,especially in light of the material mismatch issues noted above. Inorder for the winches 10,10′ to fit a double-L track with a moreintimate fit, plates and other structures would have to be welded to theframes where needed, or added-thickness plates would need to be used toweld the frame or in the bended frame, and/or other time-consumingprocessing would be required, and this has not been done owing toeconomic constraints and/or because others have not recognized thisproblem of using steel winches on aluminum winch tracks.

SUMMARY

In accordance with a first aspect of the present development, a winchfor a cargo restraining strap includes: a frame including: (i) a base;(ii) first and second parallel spaced sidewalls extending from the base,the first and second sidewalls defining respective first and secondapertures; (iii) a protective wall extending from the base and spacedfrom the first sidewall, wherein the first sidewall and said protectivewall cooperate to define a clevis structure including a channel definedbetween the first sidewall and the protective wall; a pawl movablysecured to the frame, wherein an inner end of the pawl is located in thechannel of said clevis structure; a spool extending between the firstand second sidewalls and rotatably supported in the first and secondapertures; and, a ratchet wheel connected to the aid spool and locatedadjacent the first sidewall, wherein the ratchet wheel is selectivelyengaged by the pawl.

In accordance with another aspect of the present development, a trailerincludes a winch-receiving structure and a winch slidably connected tosaid winch-receiving structure. The winch comprises: a winch framedefined as a one-piece aluminum alloy member, the winch frame comprisinga base adapted to be slidably received on the winch-receiving structureand comprising first and second sidewalls that project from the base. Apawl is pivotally secured to the frame. A spool for holding anassociated cargo strap is provided and includes a first end and a secondend. A portion of the first end of the spool extends through the firstsidewall and a portion of the second end of the spool extends throughthe second sidewall. The spool is rotatably supported by the first andsecond sidewalls. A ratchet wheel connected to the first end of thespool and located adjacent the first sidewall. The ratchet wheel ispositioned for selective engagement by the pawl, wherein the ratchetwheel and spool, when engaged by the pawl, are rotatable in onedirection only.

In accordance with another aspect of the present development, a methodof manufacturing a winch for a cargo retaining strap comprising thesteps of: extruding a one-piece aluminum alloy workpiece having a base,parallel first and second spaced apart sidewalls connected to the base,a protective outer wall arranged parallel to and spaced apart from thefirst sidewall, wherein said first sidewall and said protective outerwall define a channel therebetween. The method further includesmachining the workpiece to define a slot in the base for slidablyreceiving a winch mounting structure of an associated trailer. Themethod further includes machining the workpiece to define alignedapertures in the first and second sidewalls and inserting a spool forretaining an associated cargo strap into the aligned apertures of thefirst and second sidewalls, wherein the spool comprises a ratchet wheelconnected thereto. The method further includes pivotally securing atleast part of a pawl in the channel, wherein the aid pawl is selectivelyengaged with the ratchet wheel to allow rotation of the ratchet wheeland the spool in a first direction in a ratchet-like fashion and toprevent rotation of the ratchet wheel and spool in a second direction.

BRIEF DESCRIPTION OF THE DRAWINGS

A winch for cargo-retaining strap formed in accordance with the presentdevelopment comprises various components and arrangements of components,and is constructed according to various steps, preferred embodiments ofwhich are disclosed herein with reference to the drawings, wherein:

FIG. 1 (prior art) shows a known winch with a welded, multi-componentsteel frame;

FIG. 2 (prior art) shows a known winch with a one-piece steel frame;

FIGS. 2A,2B,2C (prior art) respectively show examples of differentprofiles of conventional extruded aluminum alloy winch tracks T1,T2,T3on which the steel winches of FIGS. 1 and 2 are commonly used;

FIG. 3A is a front elevational view of a winch formed in accordance withthe present development (the pawl is not shown to simplify the drawing);

FIG. 3B is left side elevational view of the winch shown in FIG. 3A andshowing the pawl;

FIG. 3C is similar to FIG. 3B, but shows the pawl disengaged from theratchet wheel;

FIG. 3D is a view as taken along view line 3D-3D of FIG. 3A, showing thewinch frame only for clarity;

FIGS. 4A and 4B are front and left side elevational views of an extrudedaluminum workpiece from which the frame of the winch of FIGS. 3A-3C isdefined;

FIG. 5 shows the workpiece of FIGS. 4A and 4B machined to define a frameof the winch of FIG. 3A-3C and partially shows a flanged side-rail onwhich the winch is adapted to be slidably mounted;

FIG. 6A shows the workpiece of FIGS. 4A and 4B machined to define analternative frame that is identical to that shown in FIG. 5, but that isadapted to be slidably mounted on a double-L track which is partiallyshown;

FIGS. 6B, 6C, and 6D (prior art) respectively illustrate alternativeextruded double-L track profiles;

FIGS. 7A and 7B are front and side views of an extruded aluminumworkpiece from which the one-piece spool and ratchet wheel of the winchof FIGS. 3A-3C is defined;

FIG. 7C shows the one-piece spool and ratchet wheel of the winch ofFIGS. 3A-3C;

FIG. 8 illustrates a multi-piece spool and ratchet wheel assembly thatcan be used as an alternative to the one-piece spool and ratchet wheelof FIG. 7C;

FIG. 9A is a front elevational view of a low-profile winch formed inaccordance with the present development;

FIG. 9B is a left side elevational view of the winch of FIG. 9A asslidably engaged with an associated flanged side rail;

FIG. 9C is a front elevational view that is identical to FIG. 9A,without showing the pawl to aid in understanding the structure of thewinch; and,

FIG. 9D is a view as taken along view line 9D-9D of FIG. 9C, showing thewinch frame only for clarity.

DETAILED DESCRIPTION

A winch for a cargo-retaining strap formed in accordance with thepresent development is shown generally at 100 in FIGS. 3A-3C. The winchcomprises a one-piece extruded aluminum alloy frame 120 comprising abase 122 and first and second parallel spaced-apart legs or sidewalls124 a,124 b that project outwardly from a first side 122 f the base. Asuitable aluminum alloy (sometimes referred to herein simply as“aluminum”) for defining the frame 120 is 6061-T6 but others can be usedwithout departing from the present invention, e.g., 6063 aluminum alloyor aircraft-grade aluminum alloys such as 7005, each with suitableheat-treatment. The frame 120 could also be defined as a one-piecealuminum alloy casting if desired. The frame 120 is shown by itself inFIG. 3D.

The legs 124 a,124 b define respective aligned apertures 125 a,125 b,and first and second ends 126 a,126 b of a spool 126 are rotatablysupported respectively in these apertures, and the spool extends betweenand through the legs 124 a,124 b. In the illustrated example, the spoolcomprises a slot 126 s defined therein, and a conventionalcargo-retaining strap S (typically fitted with a flat or other stylehook at its opposite distal end) is inserted in the slot 126 a and iswound around the spool for use/storage.

As described above in relation to the conventional winches 10,10′, thestrap S is payed-out from the spool 126 as needed by counter-clockwiserotation of the spool 126, and retracted as needed by clockwise rotationof the spool 126. A ratchet wheel 128 is connected to the spool 126(preferably but not necessarily as a one-piece construction) and rotateswith the spool 126 adjacent an outer face 124 o of sidewall 124 a.

A pawl 130 (FIG. 3B) pivots between a first position (FIG. 3B), where itengages the ratchet wheel 128 and prevents counter-clockwise rotation ofthe ratchet wheel and spool 126 but allows clockwise rotation for straptightening operations, and a second position (FIG. 3C), where it isdisengaged from the ratchet wheel 128 to allow free rotation of theratchet wheel and spool in either direction. The pawl 130 is normallypositioned in its first position by force of gravity. The pawl 130 ispreferably defined as a one-piece aluminum extrusion.

It is important to note that the one-piece aluminum alloy frame 120defines a clevis structure 131 (FIG. 3A) comprising the sidewall 124 aand an outer, protective wall 124 c that cooperate to define a channel134 therebetween. Aligned apertures 133 a,133 c are defined respectivelyin the walls 124 a,124 c. An inner end of the pawl 130 is located in thechannel 134 with minimal clearance between the walls 124 a,124 c toprevent lateral movement of the pawl in the channel 134 between thewalls 124 a,124 c while still allowing for the required operativepivoting movement of the pawl 130 between its first and second operativepositions. The fastener 132, which can be a bolt, pin, rivet or the likeis connected to and extends between the sidewall 124 a and outer wall124 c, passing through their respective apertures 133 a,133 c. As shown,the fastener 132 comprises a straight pin that is friction-fit into theapertures 133 a,133 c. The fastener 132 is preferably defined fromstainless-steel or other corrosion-resistant metal. It can be seen thatthe fastener engages the frame 120 at two locations on opposite sides ofthe pawl 130, i.e., the wall 124 a and the wall 124 c, for addedstrength and to evenly distribute loads from the ratchet wheel 128throughout the frame 120. As shown in FIG. 3A, the ratchet wheel 128 isaligned with the channel 134 so as to be operably located to be engagedby the pawl 130. The ratchet wheel 128 and pawl 130 preferable havematched widths so as to prevent the ratchet wheel from exerting unevenloads on the pawl and fastener 132, and this width is significantlywider than the widths of the ratchet wheel and pawl of conventionalsteel winches, e.g., 1″ widths for the ratchet wheel 128 and pawl 130 asopposed to ⅝″ widths for the ratchet wheel and pawl of conventionalwinches. Those of ordinary skill in the art will recognize that theclevis structure 131 by which the pawl 130 is secured to the frame 120by a fastener that engages the frame 120 in two locations on oppositesides of the pawl 130 is far superior to any known structure where thepawl is secured to only one location of the frame. It has been foundthat the pawl 30 of conventional prior-art winches 10,10′ is susceptibleto deflection under high loads which leads to misalignment with theassociated ratchet wheel 28 which, in turn, leads to uneven loads andfurther deflection (or complete detachment) of the pawl 30 and/or damageto the teeth of the ratchet wheel, all resulting in failure of the winch10,10′. The clevis structure 131 of the winch 100 ensures that the pawl130 is unable to deflect out of alignment with the ratchet wheel 128and, as such, the engagement between the pawl 130 and ratchet wheel 128is optimized. The clevis structure 131 and channel 134 thereof alsoserve to house the pawl 130 and protect same and the pivoting interfacewith the fastener 132 from dirt, ice, salt and other contaminants.

The ratchet wheel 128 is larger in diameter as compared to the aperture125 a defined in frame sidewall 124 a and, as such, cannot passtherethrough. The opposite end 126 c of the spool 126 projects outwardlyfrom the sidewall 124 b through aperture 125 b. This end 126 c of thespool is captured to the frame 120 by suitable means that prevent itswithdrawal through the aperture 125 b. In the illustrated embodiment, anextruded aluminum collar 127 comprising a bore 127 b is fitted to theend 126 c of the spool 126 and located closely adjacent the sidewall 124b. The collar 127 is secured to the end 126 c of spool 126 by welding orother means. The collar 127 is enlarged relative to the aperture 125 band is unable to pass therethrough. In this manner, the spool 126 iscaptured to the frame 120, and movement of the spool laterally betweenthe sidewalls 124 a,124 b is minimized owing to the closeness between:(i) the ratchet wheel 128 and the outer face 124 o of sidewall 124 a;and, (ii) the collar 127 and the sidewall 124 b.

The collar 127 defines a driving head by which the spool 126 is rotated.The collar 127 can define flats or other structures for being engaged bya tool. In the illustrated embodiment, however, first and secondintersecting bores B1,B2 are defined through the collar 127 andunderlying spool end 126 c and are arranged transversely to each other,e.g., at 90°. A winch bar or similar tool (not shown) is inserted in oneof the bores B1,B2 for purposes of rotating the spool 126.

The frame 120 is defined as a one-piece aluminum extrusion. As shown inFIG. 3A, the aluminum extrusion is advantageous in that it allows forplacement of aluminum material in the desired regions while stillkeeping a one-piece structure, so that the base 122 defines a footprintor maximum width W100 that is much larger that the maximum width W200defined inclusively between the sidewalls 124 a,124 b so as to moreevenly distribute loads from the strap S to the aluminum structure towhich the winch 100 is connected during use, e.g., an extruded aluminumdouble-L track or extruded aluminum side-rail of a flat-bed trailer. Inthe illustrated embodiment, the width W100 is about 50% larger than thewidth W200.

FIGS. 4A and 4B illustrate a raw extruded aluminum workpiece WP fromwhich the frame 120 is defined by machining and/or other conventionalprocessing to remove undesired material. The workpiece WP is extrudedwith the profile as shown in FIG. 4A and cut to length WL as shown inFIG. 4B. The profile of the workpiece WP as shown in FIG. 4A correspondsto the profile of the finished frame 120 and, thus, comprises theabove-described profile (with corresponding section labeled using aprimed (′) suffix) including a base portion 122′, sidewall portions 124a′,124 b′, an outer protective wall portion 124 c′, and channel 134′.The completed frame 120 is constructed by machining or otherwiseprocessing the workpiece WP to have the shape as shown in FIGS. 5 or 6Aor otherwise as desired. The aluminum alloy workpiece WP as shown inFIGS. 4A and 4B can also be cast if desired. The use of a cast orextruded workpiece allows for the aluminum alloy material to be placedexactly where needed for added strength and/or functionality, withoutrequiring undesirable bending or welding operations.

FIGS. 3D and 5 illustrate a first embodiment of the frame 120, whereinthe base portion 122′ of the extruded workpiece WP has been machined todefine the second side 122 s of the base 122 of the frame 120 with aslot SRL adapted to slidably receive a winch mounting structure of atrailer such as an extruded aluminum flanged side-rail SR of a flat-bedtrailer or other cargo bed with a perfect intimate fit without gapsbetween the rail SR and the base 122 of the frame 120 (of course the fitis such that the base 122 can slide on rail SR). The sidewall portions124 a′,124 b′ of the workpiece have each been machined to define arounded end 124 e and also to define the apertures 125 a,125 b in whichthe spool 126 is rotatably supported. The workpiece WP has been furthermachined to define the apertures 133 a,133 c and the outer wall 124 chas been machined to define a ratchet wheel recess 129 to provideclearance for the ratchet wheel 128 to move into abutment with outerface 124 o of wall 124 a when spool 126 is inserted into the alignedapertures 125 a,125 b during assembly.

FIG. 6A illustrates a second embodiment of the frame 220, which isidentical to the frame 120 except as otherwise shown and/or described.More particularly, the frame 220 is identical to the frame 120, exceptthat the base portion 122′ of the extruded workpiece WP has beenmachined to define the base 222 of frame 220 to include first and secondslots SL1,SL2 adapted to mate slidably and intimately with a winchmounting structure comprising an extruded double-L track LL1 defined asa part of or connected to a cargo trailer or cargo bed. It can be seenthat the slots SL1,SL2 of base 222 and track LL-1 are matched for aperfect sliding fit with minimal gaps between the base 222 and trackLL-1 as could lead to uneven transfer of loads from the frame 220 to thetrack LL-1. FIGS. 6B, 6C, and 6D respectively illustrate alternativeextruded double-L track profiles LL-2,LL-3,LL-4 and the workpiece base122′ can be machined with the required slots to perfectly slidably matewith these and other extruded track profiles (double-L, T-shaped, orother).

For added strength and in order to eliminate the need to weld orotherwise affix the ratchet wheel 128 to the spool 126, it is mostpreferred that the spool 126 and ratchet wheel 128 be defined as aone-piece construction. One example of this is shown in FIG. 7C, whereinthe spool 126 and ratchet wheel 128 are defined as a one-piece aluminumextrusion. This is accomplished by extruding a workpiece WP2 having theprofile of the ratchet wheel 128 along its entire length as shown inFIGS. 7A and 7B (note that the workpiece WP2 typically will be extrudedwith a central bore WPB that facilitates subsequent machining operationsbut need not be). The workpiece WP2 is then machined or otherwiseprocessed to remove excess material along the broken lines of FIG. 7A soas to leave behind the one-piece spool and ratchet wheel structure shownin FIG. 7C. The slot 126 a and/or bores B1,B2 for the winch bar are alsodefined if desired for a particular embodiment but are not absolutelyrequired in all cases (bores B1,B2 are typically machined only aftercollar 127 is welded or otherwise affixed to the spool 126).

The winch 100 can comprise a multi-piece spool and ratchet wheelassembly that can be used as an alternative to the one-piece spool andratchet wheel of FIG. 7C. As shown in FIG. 8, an extruded aluminumratchet wheel 128′ is welded to a spool 126′. To increase resistance toseparation of the ratchet wheel 128′ from the spool 126′ during useunder severe torsional loads due to weld failure, it is preferred thatthe end 126 d′ of spool be defined with a non-circular cross-section(e.g., square, diamond, splined, hexagonal, etc.) and that the ratchetwheel 128′ define a mating aperture 128 d′ that receives the mating end126 d′ of the spool with a non-rotatable key-like fit. The spool 126′and ratchet wheel 128′ are welded at this interface and, owing to themechanical inter-fit as described, the shear forces exerted between thespool 126′ and ratchet wheel 128′ are transmitted between thesecomponents directly and not solely through the weld as would could leadto weld failure.

An aluminum alloy winch 100 as disclosed herein is deemed superior toconventional steel winches, such as the winches 10,10′, for numerousreasons. The winch 100 is much lighter-weight as compared toconventional steel winches, even accounting for increased materialusage. It is well known that common steels used for manufacture ofconventional winches weigh about three-times more than common aluminumalloys per unit of volume. As such, even though the winch 100 has anincreased footprint width W100 and other material additions as comparedto conventional steel winches, a winch 100 will commonly weigh at least30-40% less than a conventional steel winch. This weight advantage ismultiplied by the number of winches (e.g., 16 winches) connected to thetrailer or cargo bed. Furthermore, the winch 100 will not rust in themanner of a steel winch 10,10′. The winch 100 is made from an aluminumalloy that is identical to or similar to the alloys used to manufacturethe trailer or cargo bed on which the winch will be deployed, and thushas the same or very similar hardness and elasticity properties whichhas been found to reduce damage to the structure of the trailer or othercargo bed to which the winch 100 is connected during use. The extruded(or cast) structure of the winch frame, as compared to a simple U-shapedsteel plate structure, enables a one-piece construction of complex shapethat has a footprint width W100 much greater than the width of thesidewalls 124 a,124 b so as to more evenly distribute loads from thestrap S to the aluminum trailer or other structure to which the winch100 is connected during use. Those of ordinary skill in the art willrecognize that the clevis structure 131 by which the pawl 130 is securedto the frame 120 by a fastener that engages the frame 120 in twolocations on opposite sides of the pawl 130 is far superior to any knownstructure where the pawl is secured to only one location of the frame.

Conventional steel winches are painted, and the paint coating quicklypeels off under normal use. In contrast, the frame 120 and preferablyall other components of the aluminum alloy winch 100 are anodized toprovide an aesthetically pleasing, corrosion resistant outer surface.Anodizing is a well-known electrochemical process that thickens andtoughens the naturally occurring protective aluminum oxide on thealuminum alloy parts. The resulting finish is extremely hard and is anintegral part of the metal, but has a porous structure which can becolored if desired. Those of ordinary skill in the art will recognizethat the ability to anodize the winch 100 rather than paint sameprovides another main advantage as compared to conventional steelwinches.

A low-profile winch for a cargo-retaining strap formed in accordancewith the present development is shown generally at 300 in FIGS. 9A, 9Band 9C (FIG. 9C is identical to FIG. 9A except that the pawl and itsfastener are not shown for clarity). The winch 300 is identical to thewinch 100, except as otherwise shown and/or described herein. As such,like components relative to the winch 100 are identified with likereference numbers that are 100 greater than those used to identifyfeatures of the winch 100. A low-profile winch 300 is desirable forapplications where a full height winch 100 will interfere with tires orother structures of a trailer or other cargo bed on which the winch ismounted.

The winch 300 comprises a one-piece extruded aluminum alloy frame 320comprising a base 322 and first and second parallel spaced-apart legs orsidewalls 324 a,324 b that project outwardly from the base. The legs 324a,324 b define respective aligned apertures 325 a,325 b (FIG. 9C), and aspool 326 is rotatably supported in these apertures and extends betweenand through the legs 324 a,324 b. In the illustrated example, the spoolcomprises a slot 326 s defined therein, and a conventionalcargo-retaining strap S is inserted in the slot 326 s and is woundaround the spool for use/storage. A toothed ratchet wheel 328 to beengaged by the pawl 330 is connected to the spool 326 to rotatetherewith, either by welding or other means as described in relation toFIG. 8 or as a one-piece construction as described in relation to FIGS.7A, 7B, 7C.

A pawl 330 (omitted from FIG. 9C for clarity) pivots between a firstposition (FIGS. 9A, 9B), where it engages the ratchet wheel 328 andprevents counter-clockwise rotation of the ratchet wheel and spool 326but allows ratcheting clockwise rotation for strap tighteningoperations, and a second position (shown in broken lines in FIG. 9B),where it is disengaged from the ratchet wheel 328 to allow free rotationof the ratchet wheel and spool in either direction. The pawl 330 isnormally positioned in its first position by force of gravity and/ormanual movement by a user. The pawl 330 is preferably defined as aone-piece aluminum extrusion.

The one-piece aluminum alloy frame 320 defines a clevis structure 331comprising the sidewall 324 a and an outer, protective wall 324 c thatcooperate to define a channel 334 therebetween. Aligned apertures 333a,333 c (FIG. 9C) are defined respectively in the walls 324 a,324 c. Aninner end of the pawl 330 is located in the channel 334 with minimalclearance between the walls 324 a,324 c to minimize lateral movement ofthe pawl in the channel 334 between the walls 324 a,324 c while stillallowing for the required operative pivoting movement of the pawl 330between its first and second operative positions. The fastener 332,which can be a bolt (as shown), pin, rivet or the like is connected toand extends between the sidewall 324 a and outer wall 324 c, passingthrough their respective apertures 333 a,333 c. The fastener 332 ispreferably defined from stainless-steel or other corrosion-resistantmetal. It can be seen that the fastener 332 engages the frame 320 at twolocations on opposite sides of the pawl 330, i.e., the wall 324 a andthe wall 324 c, for added strength and to evenly distribute loads fromthe ratchet wheel 328 throughout the frame 320 as described above inrelation to the winch 100. As shown in FIG. 9A, the ratchet wheel 328 isaligned with the channel 334 so as to be operably located to be engagedby the pawl. 330. The ratchet wheel 328 and pawl 330 preferable haveclosely matched widths so as to prevent the ratchet wheel from exertinguneven loads on the pawl 330 and/or fastener 332.

The winch 300 defines a height H (FIG. 9A) that is less than acorresponding height measurement of the winch 100 and, as such, isdeemed a low-profile winch. By comparing FIG. 9B with FIG. 3B, those ofordinary skill in the art will recognize that this low-profile structureis accomplished by shortening the walls 324 a,324 b, shifting the spool326 and ratchet wheel 328 inward toward the base 322 and by shifting thepawl 330 and fastener 332 forward/outward relative to a vertical plane Vthat extends through the rotational axis of the spool/ratchet wheel326/328 so that the pivot axis P for the pawl 330 is far offset from theplane V. The pawl 330 and its pivot axis P are also shifted inwardtoward the base 322. This relocation of the pawl 330 is allowed by thefact that the base 322 defined a depth D that is greater than acorresponding measurement of the winch 100. Also, the channel 334defined by the clevis structure 331 is machined to include a pawl recess334 p in which the pawl 330 is located. The recess 334 p extendsinwardly above the rail-receiving slot SRL (or slots SL1,SL2 or othermounting slot(s) defined in base 322) and, thus, allows part of theinner end of the pawl 330 also to be located inward relative to therail-receiving slot SRL (or slots SL1,SL2 or other mounting slot(s)defined in base 322) as opposed to the winch 100, where the entirechannel 134 and pawl 130 are located outward from the slot SRL (or slotsSL1,SL2 or other mounting slot(s) defined in base 322). To allow maximummovement of the spool 326 and ratchet wheel 328 inward toward base 322to provide a reduced height H, and unlike conventional winches, theentire pawl 330 and fastener 332 for same are shifted laterally awayfrom vertical plane V so that, preferably, no part of pawl 330 and/orfastener 332 are located between the ratchet wheel 328 and therail-receiving slot SRL (or slots SL1,SL2 or other mounting slot(s)defined in base 322). To prevent the cargo strap S from rubbing on thebase 322 of frame 320, the frame preferably comprises a recess 322 r(see FIG. 9D) defined in the base 322 between the first and secondsidewalls 324 a,324 b.

The invention has been described with reference to preferredembodiments. Modifications and alterations will occur to those ofordinary skill in the art to which the invention pertains upon readingthis specification, and it is intended that the invention be construedas encompassing these modifications and alterations to the maximumpossible extent.

1. A winch for a cargo restraining strap, said winch comprising: aone-piece aluminum alloy frame including: (i) a base; (ii) first andsecond parallel spaced sidewalls extending from said base, said firstand second sidewalls defining respective first and second apertures;(iii) a protective wall extending from said base and spaced from saidfirst sidewall, wherein said first sidewall and said protective wallcooperate to define a clevis structure including a channel definedbetween said first sidewall and said protective wall; a pawl pivotablysecured between said protective wall and said first sidewall of saidframe, wherein an inner end of said pawl is located in said channel ofsaid clevis structure between said protective wall and said firstsidewall, said pawl manually movable between first and second positions;a spool extending between said first and second sidewalls and rotatablysupported in the first and second apertures; and, a ratchet wheelconnected to said spool and located adjacent said first sidewall,wherein said pawl engages said ratchet wheel and prevents movement ofthe ratchet wheel in one rotational direction when said pawl is pivotedto said first position, and wherein said pawl is disengaged from saidratchet wheel when said pawl is pivoted to said second position.
 2. Thewinch as set forth in claim 1, wherein said base further comprises aslot defined therein and adapted to engage an associated trailerstructure.
 3. The winch as set forth in claim 1, wherein said one-piecealuminum alloy frame is defined by a one-piece extruded member.
 4. Thewinch as set forth in claim 1, wherein said spool and said ratchet wheelare defined from aluminum alloy.
 5. The winch as set forth in claim 4,wherein said spool and said ratchet wheel are defined together as asingle one-piece construction.
 6. The winch as set forth in claim 5,wherein said spool and ratchet wheel comprise an aluminum extrusion. 7.The winch as set forth in claim 1, wherein said first and secondsidewalls define inclusively therebetween a width, and wherein said basedefines a footprint width that is greater than said width definedinclusively between said first and second sidewalls.
 8. A which for acargo restraining strap, said winch comprising: a frame including: (i) abase; (ii) first and second parallel spaced sidewalls extending fromsaid base, said first and second sidewalls defining respective first andsecond apertures; (iii) a protective wall extending from said base andspaced from said first sidewall, wherein said first sidewall and saidprotective wall cooperate to define a clevis structure including achannel defined between said first sidewall and said protective wall; apawl movably secured to said frame, wherein an inner end of said pawl islocated in said channel of said clevis structure, wherein said pawl issecured to said frame by a fastener that extends through said channel ofsaid clevis structure and that is engaged with said protective wall andsaid first sidewall; a spool extending between said first and secondsidewalls and rotatably supported in the first and second apertures;and, a ratchet wheel connected to said spool and located adjacent saidfirst sidewall, wherein said ratchet wheel is selectively engaged bysaid pawl.
 9. The winch as set forth in claim 8, wherein said fasteneris defined from stainless steel.